Multi-omics reveals hypertrophy of adipose tissue and lipid metabolism disorder via mitochondria in young mice under real-ambient exposure to air pollution

Diabetes burden attributable to air pollution from 1990~2021 and the future trends: a population-based study

Background

This investigation explores the worldwide impact of diabetes burden associated with air pollution, drawing on data from the Global Burden of Disease Study 2021.

Method

The influence of air pollution on diabetes burden was analyzed at global, regional, and national levels. The study considered variations across age groups and genders and explored the relationship between disease impact and the Socio-Demographic Index (SDI). Additionally, an ARIMA model was employed to predict the future incidence of diabetes burden related to air pollution until 2050.

Result

In 2021, approximately 281.91 thousand fatalities and 12.90 million disability-adjusted life years were attributed to diabetes burden due to air pollution, featuring an age-standardized mortality rate (ASMR) of 3.3234 (95% UI, 1.9549-4.6634) and an age-standardized DALY rate (ASDR) of 148.9167 (95% UI, 86.5013-224.9116) per 100,000 individuals. There was a noticeable escalation in the disease burden over the period studied. The most severe effects were noted in individuals aged 60 and above. The data also revealed a higher disease burden among males. Forecasting suggests that while low SDI regions might see a decrease in death rates, lower-middle SDI areas could face an increase in standardized mortality rates. On a national scale, Russia, Mexico, and several African nations are predicted to experience rising diabetes burden attributable to air pollution mortality rates and age-standardized mortality rates from now to 2050. South Asia and Africa are anticipated to witness substantial growth in age-standardized death rates compared to other areas.

Conclusion

The results provide essential insights for developing preventive strategies for diabetes burden and measures to mitigate air pollution.

Association of metabolic signatures of air pollution with MASLD: Observational and Mendelian randomization study

BACKGROUND & AIMS

Air pollution is a significant public health issue and an important risk factor for metabolic dysfunction-associated steatotic liver disease (MASLD), though the underlying mechanisms of this association are unknown. Herein, we aimed to identify metabolic signatures associated with exposure to ambient air pollution and to explore their associations with the risk of MASLD.

METHODS

We utilized data from the UK Biobank cohort. Annual mean concentrations of PM2.5, PM10, NO2 and NOx were assessed for each participant using bilinear interpolation. The elastic net regression model was used to identify metabolites associated with four air pollutants and to construct metabolic signatures. Associations between air pollutants, metabolic signatures and MASLD were analyzed using Cox models. Mendelian randomization (MR) analysis was used to examine potential causality. Mediation analysis was employed to examine the role of metabolic signatures in the association between air pollutants and MASLD.

RESULTS

A total of 244,842 participants from the UK Biobank were included in this analysis. We identified 87, 65, 76, and 71 metabolites as metabolic signatures of PM2.5, PM10, NO2, and NOx, respectively. Metabolic signatures were associated with risk of MASLD, with hazard ratios (HRs) and 95% CIs of 1.10 (1.06-1.14), 1.06 (1.02-1.10), 1.24 (1.20-1.29) and 1.14 (1.10-1.19), respectively. The four pollutants were associated with increased risk of MASLD, with HRs (95% CIs) of 1.03 (1.01-1.05), 1.02 (1.01-1.04), 1.01 (1.01-1.02) and 1.01 (1.00-1.01), respectively. MR analysis indicated an association between PM2.5, NO2 and NOx-related metabolic signatures and MASLD. Metabolic signatures mediated the association of PM2.5, PM10, NO2 and NOx with MASLD.

CONCLUSION

PM2.5, PM10, NO2 and NOx-related metabolic signatures appear to be associated with MASLD. These signatures mediated the increased risk of MASLD associated with PM2.5, PM10, NO2 and NOx.

IMPACT AND IMPLICATIONS

Air pollution is a significant public health issue and an important risk factor for metabolic dysfunction-associated steatotic liver disease (MASLD), however, the mechanism by which air pollution affects MASLD remains unclear. Our study used integrated serological metabolic data of 251 metabolites from a large-scale cohort study to demonstrate that metabolic signatures play a crucial role in the elevated risk of MASLD caused by air pollution. These results are relevant to patients and policymakers because they suggest that air pollution-related metabolic signatures are not only potentially associated with MASLD but also involved in mediating the process by which PM2.5, PM10, NO2, and NOx increase the risk of MASLD. Focusing on changes in air pollution-related metabolic signatures may offer a new perspective for preventing air pollution-induced MASLD and serve as protective measures to address this emerging public health challenge.

Air pollution exposure and prevalence of non-alcoholic fatty liver disease and related cirrhosis: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

A systematic review and meta-analysis were used to investigate the relationship between air pollution exposure and the prevalence of non-alcoholic fatty liver disease (NAFLD) and its related cirrhosis. Through this study, we hope to clarify the potential public health risks of air pollution as an environmental exposure factor.

METHODS

Through a comprehensive and systematic search of the EMBASE, PubMed, Web of Science, and Cochrane library databases, studies published up to March 30, 2024, that met the eligibility criteria were identified. The meta-analysis aimed to determine the association between air pollution exposure and NAFLD risk. Subgroup analyses were conducted based on regional economic development after adjusting for confounding factors. The combined odds ratio (OR) was calculated, publication bias was assessed using funnel plots, and consideration was given to heterogeneity among study-specific relative risks.

RESULTS

This review included 14 observational studies (including 7 cohort studies and 7 cross-sectional studies) involving 43,475,41 participants. The pooled analysis showed that PM2.5, NOx, PM10, PM2.5-10, passive smoking, PM1, and air pollution from solid fuels were positively associated with the incidence and prevalence of NAFLD and its related cirrhosis. The risk ratios for PM2.5, NOx, PM10, PM2.5-10, passive smoking, and air pollution from solid fuels for NAFLD and its related cirrhosis were 1.33 (95 % CI: 1.25, 1.42), 1.19 (95 % CI: 1.14, 1.23), 1.27 (95 % CI: 1.05, 1.55), 1.05 (95 % CI: 1.00, 1.11), 1.53 (95 % CI: 1.12, 2.09), 1.50 (95 % CI: 0.86, 2.63), and 1.18 (95 % CI: 0.85, 1.63), respectively. In contrast, the risk ratio for O3 was 0.75 (95 % CI: 0.69, 0.83), suggesting that O3 may lower the incidence and prevalence of NAFLD and its related cirrhosis. We also conducted subgroup analyses based on the level of national development to examine the impact of PM2.5 on NAFLD and its related cirrhosis. The results showed that the risk of NAFLD and its related cirrhosis associated with PM2.5 in developing countries was 1.41 (95 % CI: 1.29, 1.53), which was higher than 1.20 (95 % CI: 1.12, 1.29) in developed countries.

CONCLUSION

The study findings show that PM2.5, NOx, PM10, PM2.5-10, passive smoking, PM1, and air pollution from solid fuels can increase an individual's risk of developing NAFLD and its related cirrhosis; while O3 can reduce the risk. In developing countries, the risk level of NAFLD and its related cirrhosis due to PM2.5 is higher than that in developed countries.

Constructing an adverse outcome pathway framework for the impact of maternal exposure to PM2.5 on liver development and injury in offspring

Ambient fine particulate matter (PM2.5) is a significant contributor to air pollution. PM2.5 exposure poses a substantial hazard to public health. In recent years, the adverse effects of maternal PM2.5 exposure on fetal health have gradually gained public attention. As the largest organ in the body, the liver has many metabolic and secretory functions. Liver development, as well as factors that interfere with its growth and function, are of concern. This review utilized the adverse outcome pathway (AOP) framework as the analytical approach to demonstrate the link between maternal PM2.5 exposure and potential neonatal liver injury from the molecular to the population level. The excessive generation of reactive oxygen species (ROS), subsequent endoplasmic reticulum (ER) stress, and oxidative stress were regarded as the essential components in this framework, as they could trigger adverse developmental outcomes in the offspring through DNA damage, autophagy dysfunction, mitochondrial injury, and other pathways. To the best of our knowledge, this is the first article based on an AOP framework that elaborates on the influence of maternal exposure to PM2.5 on liver injury occurrence and adverse effects on liver development in offspring. Therefore, this review offered mechanistic insights into the developmental toxicity of PM2.5 in the liver, which provided a valuable basis for future studies and prevention strategies.

Mitochondrial dysfunction induced by ambient fine particulate matter and potential mechanisms

Air pollution is one of the major environmental threats contributing to the global burden of disease. Among diverse air pollutants, fine particulate matter (PM2.5) poses a significant adverse health impact and causes multi-system damage. As a highly dynamic organelle, mitochondria are essential for cellular energy metabolism and vital for cellular homeostasis and body fitness. Moreover, mitochondria are vulnerable to external insults and common targets for PM2.5-induced cellular damage. The resultant impairment of mitochondrial structure and function initiates the pathogenesis of diverse human diseases. This review mainly summarizes the in vivo and in vitro findings of PM2.5-induced mitochondrial dysfunction and its implication in PM2.5-induced health effects. Furthermore, recent advances toward the underlying mechanisms of PM2.5 and its components-induced mitochondrial dysfunction are also discussed, with an attempt to provide insights into the toxicity of PM2.5 and basic information for devising appropriate intervention strategies.

Silibinin inhibits PM2.5-induced liver triglyceride accumulation through enhancing the function of mitochondrial Complexes I and II

Background

The standardized extract of milk thistle seeds, known as silibinin, has been utilized in herbal medicine for over two centuries, with the aim of safeguarding the liver against the deleterious effects of various toxic substances. However, the role of silibinin in Particulate Matter (PM2.5)-induced intrahepatic triglyceride accumulation remains unclear. This study seeks to investigate the impact of silibinin on PM2.5-induced intrahepatic triglyceride accumulation and elucidate potential underlying mechanisms.

Methods

A model of intrahepatic triglyceride accumulation was established in male C57BL/6J mice through intratracheal instillation of PM2.5, followed by assessment of liver weight, body weight, liver index, and measurements of intrahepatic triglycerides and cholesterol after treatment with silibinin capsules. Hep G2 cells were exposed to PM2.5 suspension to create an intracellular triglyceride accumulation model, and after treatment with silibinin, cell viability, intracellular triglycerides and cholesterol, fluorescence staining for Nile Red (lipid droplets), and DCFH-DA (Reactive Oxygen Species, ROS), as well as proteomics, real-time PCR, and mitochondrial function assays, were performed to investigate the mechanisms involved in reducing triglycerides.

Results

PM2.5 exposure leads to triglyceride accumulation, increased ROS production, elevated expression of inflammatory factors, decreased expression of antioxidant factors, and increased expression of downstream genes of aryl hydrocarbon receptor. Silibinin can partially or fully reverse these factors, thereby protecting cells and animal livers from PM2.5-induced damage. In vitro studies show that silibinin exerts its protective effects by preserving oxidative phosphorylation of mitochondrial complexes I and II, particularly significantly enhancing the function of mitochondrial complex II. Succinate dehydrogenase (mitochondrial complex II) is a direct target of silibinin, but silibinin A and B exhibit different affinities for different subunits of complex II.

Conclusion

Silibinin improved the accumulation of intrahepatic triglycerides induced by PM2.5, and this was, at least in part, explained by an enhancement of oxidative phosphorylation in mitochondrial Complexes I and II.

Long-term exposure to PM2.5 chemical constituents and diabesity: evidence from a multi-center cohort study in China

Background

Long-term exposure to PM2.5 is known to increase the risks for diabetes and obesity, but its effects on their coexistence, termed diabesity, remain uncertain. This study aimed to investigate the associations of long-term exposure to PM2.5 and its chemical constituents with the risks for diabesity, diabetes, and obesity.

Methods

This cross-sectional study used the baseline data of a multi-center cohort, consisting of three provincially representative cohorts comprising a total of 134,403 participants from the eastern (Fujian Province), central (Hubei Province), and western (Yunnan Province) regions of China. Obesity and diabetes, and diabesity were identified by a body mass index (BMI) ≥28 kg/m2 and fasting plasma glucose (FPG) ≥126 mg/dL. The average concentrations of PM2.5 and five chemical constituents (NO3 -, SO4 2-, NH4 +, organic matter, and black carbon) over participants' residence during the past three years were estimated using machine learning models. Logistic regression models with double robust estimators, Bayesian kernel machine regression, and weighted quantile sum regression were employed to estimate independent and joint effects of PM2.5 chemical constituents on the risks for diabesity, diabetes, and obesity, as well as the differences from the effects on obesity. Stratified analyses were performed to examine effect modification of sociodemographic and lifestyle factors.

Findings

There were 129,244 participants with a mean age of 54.1 ± 13.8 years included in the study. Each interquartile range increase in PM2.5 concentration (8.53 μg/m3) was associated with an increased risk for diabesity (OR = 1.23 [1.17, 1.30]), diabetes only (OR = 1.16 [1.13, 1.19]), and obesity only (OR = 1.03 [1.00, 1.05]). Long-term exposure to each PM2.5 chemical constituent was associated with an increased risk for diabesity, where organic matter exposure, with maximum weight (48%), was associated with a higher risk for diabesity (OR = 1.21 [1.16, 1.27]). Among those with obesity, black carbon contributed most (68%) to the joint effect of PM2.5 chemical constituents on diabesity (OR = 1.16 [1.11, 1.22]). Physical activity reduced adverse effects of PM2.5 on diabesity. Also, additive rather than multiplicative effects of obesity on the PM2.5-diabetes association were observed.

Interpretation

Long-term exposure to PM2.5 and its chemical constituents was associated with an increased risk for diabesity, stronger than associations for diabetes and obesity alone. The main constituents associated with diabesity and obesity were black carbon and organic matter.

Funding

National Natural Science Foundation of China (42271433, 723B2017), National Key R&D Program of China (2023YFC3604702), Fundamental Research Funds for the Central Universities (2042023kfyq04, 2042024kf1024), the Science and Technology Major Project of Tibetan Autonomous Region of China (XZ202201ZD0001G), Science and technology project of Tibet Autonomous Region（XZ202303ZY0007G), Key R&D Project of Sichuan Province (2023YFS0251), Renmin Hospital of Wuhan University (JCRCYG-2022-003), Jiangxi Provincial 03 Special Foundation and 5G Program (20224ABC03A05), Wuhan University Specific Fund for Major School-level Internationalization Initiatives (WHU-GJZDZX-PT07).

Effects of PM2.5 and high-fat diet on glucose and lipid metabolisms and role of MT-COX3 methylation in male rats

Both fine particulate matter (PM2.5) and high-fat diet (HFD) can cause changes in glucose and lipid metabolisms; however, the mechanism of their combined effects on glucose and lipid metabolisms is still unclear. This study aimed to investigate the effects of PM2.5 and HFD co-exposure on glucose and lipid metabolisms and mitochondrial DNA methylation in Wistar rats. PM2.5 and HFD co-treatment led to an increase in fasting blood glucose levels, an alteration in glucose tolerance, and a decrease in high density lipoprotein cholesterol (HDL-C) levels in Wistar rats. In the homeostasis model assessment (HOMA), HOMA-insulin resistance (HOMA-IR) increased and HOMA-insulin sensitivity (HOMA-IS) and HOMA-β cell function (HOMA-β) decreased in rats co-exposed to PM2.5 and HFD. Additionally, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were increased, and interleukin-6 (IL-6) and interleukin-10 (IL-10) mRNA expressions were upregulated in the brown adipose tissue following PM2.5 and HFD co-exposure. Bisulfite pyrosequencing was used to detect the methylation levels of mitochondrially-encoded genes (MT-COX1, MT-COX2 and MT-COX3), and MT-COX3 was hypermethylated in the PM2.5 and HFD co-exposure group. Moreover, MT-COX3-Pos.2 mediated 36.41 % (95 % CI: -27.42, -0.75) of the total effect of PM2.5 and HFD exposure on HOMA-β. Our study suggests that PM2.5 and HFD co-exposure led to changes in glucose and lipid metabolisms in rats, which may be related to oxidative stress and inflammatory responses, followed by mitochondrial stress leading to MT-COX3 hypermethylation. Moreover, MT-COX3-Pos.2 was found for the first time as a mediator in the impact of co-exposure to PM2.5 and HFD on β-cell function. It could serve as a potential biomarker, offering fresh insights into the prevention and treatment of metabolic diseases.

Clustering by chemicals: A novel examination of chemical pollutants and social vulnerability in children and adolescents

BACKGROUND

Inhaled air pollutants are environmental determinants of health with negative impacts on human health. Air pollution has been linked to the incidence and progression of disease, with its effects unequally distributed across the population. Children compared to adults are a highly vulnerable group and suffer disproportionately from systemic environmental inequities exacerbated by social determinants.

OBJECTIVE

To explore air pollution cluster patterns among 6- to 19-year-olds from the 2015-2016 National Health and Nutrition Examination Survey (NHANES) and examine chemical cluster associations with social vulnerability.

METHODS

NHANES data was extracted for 697 children and adolescents. Social vulnerability characteristics from questionnaires were assembled to construct a modified social vulnerability index (SVI). Thirty-four air pollutant exposure chemicals were measured in urine and available from the laboratory sub-sample A data. K-means clustering classified the sample into three groups: low, medium, and high chemical exposure groups. Logistic regression was used to examine associations between high chemical group membership and SVI after adjusting for age, biological sex, and BMI. Complex survey analysis was conducted using SAS v9.4 to reflect population effects.

RESULTS

Air pollution clusters revealed significant differences in mean concentrations between groups for 31 analytes with minimal distinction in mixture profiles. SVI scores differed significantly between the three groups (P = .002), and with each point increase in their SVI, the odds of a child being assigned to the highest-chemical exposure group increased by 11.55% (95% CI: 1.02-1.31), after adjustment.

CONCLUSION

Unsupervised clustering of environmental sub-sample specimens from NHANES provides an innovative, multi-pollutant model that can be used to explore exposure patterns in this population. Utilizing the modified SVI allows for the identification of children that may be highly susceptible to air pollution. It is imperative to interpret the research findings in light of historical structural and discriminatory inequalities to develop beneficial and sustainable solutions.

PM2.5, component cause of severe metabolically abnormal obesity: An in silico, observational and analytical study

Obesity is currently one of the most alarming pathological conditions due to the progressive increase in its prevalence. In the last decade, it has been associated with fine particulate matter suspended in the air (PM2.5). The purpose of this study was to explore the mechanistic interaction of PM2.5 with a high-fat diet (HFD) through the differential regulation of transcriptional signatures, aiming to identify the association of these particles with metabolically abnormal obesity. The research design was observational, using bioinformatic methods and an explanatory approach based on Rothman's causal model. We propose three new transcriptional signatures in murine adipose tissue. The sum of transcriptional differences between the group exposed to an HFD and PM2.5, compared to the control group, were 0.851, 0.265, and -0.047 (p > 0.05). The HFD group increased body mass by 20% with two positive biomarkers of metabolic impact. The group exposed to PM2.5 maintained a similar weight to the control group but exhibited three positive biomarkers. Enriched biological pathways (p < 0.05) included PPAR signaling, small molecule transport, adipogenesis genes, cytokine-cytokine receptor interaction, and HIF-1 signaling. Transcriptional regulation predictions revealed CpG islands and common transcription factors. We propose three new transcriptional signatures: FAT-PM2.5-CEJUS, FAT-PM2.5-UP, and FAT-PM2.5-DN, whose transcriptional regulation profile in adipocytes was statistically similar by dietary intake and HFD and exposure to PM2.5 in mice; suggesting a mechanistic interaction between both factors. However, HFD-exposed murines developed moderate metabolically abnormal obesity, and PM2.5-exposed murines developed severe abnormal metabolism without obesity. Therefore, in Rothman's terms, it is concluded that HFD is a sufficient cause of the development of obesity, and PM2.5 is a component cause of severe abnormal metabolism of obesity. These signatures would be integrated into a systemic biological process that would induce transcriptional regulation in trans, activating obesogenic biological pathways, restricting lipid mobilization pathways, decreasing adaptive thermogenesis and angiogenesis, and altering vascular tone thus inducing a severe metabolically abnormal obesity.

Environmental PM2.5-triggered stress responses in digestive diseases

Airborne particulate matter in fine and ultrafine ranges (aerodynamic diameter less than 2.5 μm, PM2.5) is a primary air pollutant that poses a serious threat to public health. Accumulating evidence has pointed to a close association between inhalation exposure to PM2.5 and increased morbidity and mortality associated with modern human complex diseases. The adverse health effect of inhalation exposure to PM2.5 pollutants is systemic, involving multiple organs, different cell types and various molecular mediators. Organelle damages and oxidative stress appear to play a major role in the cytotoxic effects of PM2.5 by mediating stress response pathways related to inflammation, metabolic alteration and cell death programmes. The organs or tissues in the digestive tract, such as the liver, pancreas and small intestines, are susceptible to PM2.5 exposure. This review underscores PM2.5-induced inflammatory stress responses and their involvement in digestive diseases caused by PM2.5 exposure.

Influence of Air Pollution Exposures on Cardiometabolic Risk Factors: a Review

PURPOSE OF REVIEW

The increasing prevalence of cardiometabolic risk factors (CRFs) contributes to the rise in cardiovascular disease. Previous research has established a connection between air pollution and both the development and severity of CRFs. Given the ongoing impact of air pollution on human health, this review aims to summarize the latest research findings and provide an overview of the relationship between different types of air pollutants and CRFs.

RECENT FINDINGS

CRFs include health conditions like diabetes, obesity, hypertension etc. Air pollution poses significant health risks and encompasses a wide range of pollutant types, air pollutants, such as particulate matter (PM), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O2). More and more population epidemiological studies have shown a positive correlation between air pollution and CRFs. Although various pollutants have diverse effects on specific cellular molecular pathways, their main influence is on oxidative stress, inflammation response, and impairment of endothelial function. More and more studies have proved that air pollution can promote the occurrence and development of cardiovascular and metabolic risk factors, and the research on the relationship between air pollution and CRFs has grown intensively. An increasing number of studies are using new biological monitoring indicators to assess the occurrence and development of CRFs resulting from exposure to air pollution. Abnormalities in some important biomarkers in the population (such as homocysteine, uric acid, and C-reactive protein) caused by air pollution deserve more attention. Further research is warranted to more fully understand the link between air pollution and novel CRF biomarkers and to investigate potential prevention and interventions that leverage the mechanistic link between air pollution and CRFs.

Emerging technologies in adipose tissue research

Technologies are transforming the understanding of adipose tissue as a complex and dynamic tissue that plays a critical role in energy homoeostasis and metabolic health. This mini-review provides a brief overview of the potential impact of novel technologies in biomedical research and aims to identify areas where these technologies can make the most significant contribution to adipose tissue research. It discusses the impact of cutting-edge technologies such as single-cell sequencing, multi-omics analyses, spatial transcriptomics, live imaging, 3D tissue engineering, microbiome analysis, in vivo imaging, and artificial intelligence/machine learning. As these technologies continue to evolve, we can expect them to play an increasingly important role in advancing our understanding of adipose tissue and improving the treatment of related diseases.

Redox and inflammatory mechanisms linking air pollution particulate matter with cardiometabolic derangements

Air pollution is the largest environmental risk factor for disease and premature death. Among the different components that are present in polluted air, fine particulate matter below 2.5 μm in diameter (PM2.5) has been identified as the main hazardous constituent. PM2.5 mainly arises from fossil fuel combustion during power generation, industrial processes, and transportation. Exposure to PM2.5 correlates with enhanced mortality risk from cardiovascular diseases (CVD), such as myocardial infarction and stroke. Over the last decade, it has been increasingly suggested that PM2.5 affects CVD already at the stage of risk factor development. Among the multiple biological mechanisms that have been described, the interplay between oxidative stress and inflammation has been consistently highlighted as one of the main drivers of pulmonary, systemic, and cardiovascular effects of PM2.5 exposure. In this context, PM2.5 uptake by tissue-resident immune cells in the lung promotes oxidative and inflammatory mediators release that alter tissue homeostasis at remote locations. This pathway is central for PM2.5 pathogenesis and might account for the accelerated development of risk factors for CVD, including obesity and diabetes. However, transmission and end-organ mechanisms that explain PM2.5-induced impaired function in metabolic active organs are not completely understood. In this review, the main features of PM2.5 physicochemical characteristics related to PM2.5 ability to induce oxidative stress and inflammation will be presented. Hallmark and recent epidemiological and interventional studies will be summarized and discussed in the context of current air quality guidelines and legislation, knowledge gaps, and inequities. Lastly, mechanistic studies at the intersection between redox metabolism, inflammation, and function will be discussed, with focus on heart and adipose tissue alterations. By offering an integrated analysis of PM2.5-induced effects on cardiometabolic derangements, this review aims to contribute to a better understanding of the pathogenesis and potential interventions of air pollution-related CVD.